Move 'use strict' to file level

Change-Id: I1f0dae4aa168e77c112bcd3688c98b84e4ce5f36
diff --git a/dev/js/src/plugin/server.js b/dev/js/src/plugin/server.js
index 96b5cb7..19f8c5f 100644
--- a/dev/js/src/plugin/server.js
+++ b/dev/js/src/plugin/server.js
@@ -7,9 +7,9 @@
  *
  * @author Nils Diewald
  */
+"use strict";
 
 define(['plugin/widget', 'plugin/service', 'state', 'util'], function (widgetClass, serviceClass, stateClass) {
-  "use strict";
 
   KorAP.Panel = KorAP.Panel || {};